UPDATE: Microsoft, who historically have not commented on rumors at all, have since told The New York Times “The Daily story is based on inaccurate rumors and speculation.”

The question of whether a Microsoft Office app is coming to the iPad is no longer in question: it’s now a matter of when. Someone with hands-on access to an early version of the app has sent in a photo to The Daily.

Microsoft has built plenty of apps for iOS already, so it’s not too shocking that they had designs on developing an iPad version of the world’s most popular productivity suite. They had also already released a single Office app for iOS, OneNote, and that proved to be incredibly popular ever since its arrival in the App Store. Ratings have also been largely positive.

According to The Daily‘s source, Word, Excel, and PowerPoint functionality will be offered — and it would be a shock to see Microsoft go beyond these four (when you include OneNote) to offer premium apps like Access or Outlook. The design is reportedly Metro-ish, and almost certainly looks similar to what you can already see in OneNote. Swap out the purple for the other trademark colors — blue for Word, green for Excel, and orange for PowerPoint — and you’ll have a good idea how things will look.

While not mentioned, it’s also a safe bet that SkyDrive integration will be included. Microsoft’s cloud storage service already features prominently in OneNote for iOS, after all.

With the iOS waters thoroughly tested, the time will soon be at hand for Microsoft to dominate the tablet productivity app space. It’s becoming a huge opportunity for them, too, as more and more iPads infiltrate enterprise settings and compliment existing laptops and desktops that already have access to the traditional Office suite.

Office has already made its way to the web, and there’s a OneNote app for Android phones and tablets as well. It’s entirely possible that we’ll see Microsoft continue their tablet push with Office for Android, rounding out what will no doubt be the three hottest tablet platforms come the end of 2012: the iPad, Android, and Windows 8.